A time to digital converter (TDC) is a device that converts time information into a digital code. The TDC measures a time difference between features of input signals and generates a digital code corresponding to the time difference. The features may, for example, include rising edges of the signals, falling edges of the signals, logic level transitions of the signals, etc. TDCs are used in a variety of applications, such as analog to digital converters, phase locked loops, delay locked loops, image sensors, scanning devices, distance measurement devices, etc.